Process for the production of cellulosic structures



Oct. 6, 1942. w. H. CHARCH ET 'AL 2,297,746

PROCESS FOR THE PRODUCTION OF CELLULOSIC STRUCTURES Filed Oct. 17, 1940 INVENTORS William Hale Ehc-urch WiL'liamFTEdErick Underwu u 11 BY d zw/u ATTORNEY Patented Oct. 6, 1942 UNITED STATES PATENT OFFICE PROCESS FOR THE PRODUCTION OF CELLULOSIC STRUCTURES Application October 17, 1940, Serial No; 361,604

14 Claims.

This invention relates to improvements in the process of crimp-spinning crimpy filaments, threads, andthe like from viscose. This application is a continuation, in-part, of our copending application No. 180,976, filed December 21, 1937, now Patent No. 2,249,745.

The above-identified application is directed to new cellulosic filaments which possess inherent and permanent crimps in three dimensions with substantially no molecular orientation in the direction of the fiber axis, said filaments exhibiting good strength, elasticity and other desirable physical characteristics. The above said application is i'urther directed to a new process, hereinafter referred to as a crimp-spinning process, for producing such filaments, and yarns composed of such filaments, which comprises forcing fine streams of viscose through the orifices of a spinneret into a coagulating bath which will substantially completely coagulate the filaments before any substantial regeneration thereof the speed of extrusion, i. e., the jet velocity, being four or more times the rate at which the coagulated filaments are drawn off and removed from the coagulating bath. The filaments, after being removed from the coagulating bath are preferably stretched while in the Wet state to improve the character of the crimpy filaments.

As set forth in application Serial No. 180,976, the coagulating bath may be a fast coagulating, non-regenerating bath, in which case the filaments will be subjected to regeneration in a second bath. If, on the other hand, the coagulating bath has a slow or delayed regenerating action, the crimpy filaments may be spun by a single-bath process.

In the spinning of crimpy filaments by the process disclosed in the above said previously filed application, it was found that after spinning a very desirable product for a period of time, the continuation of spinning, even though conducted under exactly the same conditions of spinning, produces a filament with a gradually decreasing amount of crimp. Although this condition is objectionable in a two-bath spinning process. it is particularly objectionable in a sinale-bath process. In an extreme case in a single-bath spinning process the crimpy structure of the spun filaments may disappear in a period of time as short as ten or fifteen minutes. Consequently, heretofore, a two-bath spinning process for the crimp-spinning of filaments has been considered more economical than a single bath process, whereas the reverse should be true.

The above difiiculties presented a serious problem to overcome in the crimp-spinning of filaments by the employment of a single coagulating and regenerating bath. In order to solve this problem a very extended search was instituted for a bath composition which would overcome the difiiculty. Many difierent types of spinnerets were investigated with the object of eliminating the said problem. Attemps were made to solve the problem by modifying the viscose spinning solutions, and also by applying an electrical potential to the spinnerets. All of these several attempts, as well as other modifications of the process, failed to eliminate the above said difliculty.

The object and nature of the present invention is to overcome the above mentioned objections in the crimp-spinning of filaments.

It is a further object of this invention to provide an improved crimp-spinning process in which a crimp of uniform character will be imparted to the filaments over an extended period of time.

It is another object of this invention to dissolve, in a crimp-spinning coagulating bath, an agent which will increase the continuity of uniform crimp formation in the filaments produced by a crimp-spinning process.

The present invention will be more clearly understood by reference to the accompanying illustration in which reference numeral I3 designates a filament-forming spinneret submerged in coagulating bath I4. The filaments issuing from the spinneret are passed about guide rollers I6 and I1 and wound onto bobbin I8. The drawoff speed imparted to the filaments I5 by the bobbin does not exceed one-quarter of the jet velocity of the filament-forming composition issuing from the spinneret. As a result, th filaments will be caused to crimp substantially in the manner illustrated.

The objects of the present invention may be accomplished, in general, by crimp-spinning a viscose solution into a coagulating bath with a jet velocity-draw-off ratio of at least four, said coagulating bath having such a character as to substantially completely coagulate the resulting spun filaments before any substantial regeneration thereof, said bath containing, dissolved therein, an agent which will increase the continuity of uniform crimp formation in the resulting spun filaments. Agents suitable for use in accordance with the present invention to increase the period during which uniform crimps are formed in a crimp-spinning process shall preserving agents."

hereinafter be referred to as crimp-continuity As crimp-continuity preserving agents," it has been found that all surface-active agents which are soluble to the extent of at least 0.01%, by weight, in a 5% aqueous sulfuric acid solution are suitable for use in accordance with the present invention.

By surface-active agents is a crimp-spinning process.

The surface-active agents may be either cation-active or anion-active.

The anion-active materials are preferred largely because of economy, these materials being cheaper, in general, than the known cation-active materials.

The following classes of surface-active agents are found to be very desirable for use as crimpcontinuity preserving agents:

Table of surface-active agents which have been found, by test, to be very desirable as crimpcontinuity preserving agents.

This table indicates the general class of compounds-the trade names of the compounds, together with the name of the manufacturer, and also, as far as possible, the chemical formula of the agent Formula Trade name Manufacturer CLASS I.Sul/zmaled hydrocarbons Isopropylated uaphthyl- "Alkauol B, HG, E. I. du Pout.

ene sodium suli'ouate. SA." Tetrahydronaphthyleueso- Alkanol S" Do.

dium sulfonate. Monobutylphenylphenol sodium monosulfonate. Dibutylpheuylphenol sodium disulfonate. Monobutyldiphenyl sodium monosulfonate. Sodium abieteue sulfonate. Alkyl aryl suliouate llrv adme B, C, Ciba Co., Inc. Merpentine". E. I. du Pont. "Naccolene F" Natl. Aniline &

Chem. Co. -"Nacconol E".. Do. "Nacccuol N R Do. Naccouol NRL". Do. "NaceonolNRSF" Do. Nacconol A. Do. Nekal A, BX".-. General Dyestufis orp. Neomerpin VD E. I. du Pont. "Novonacco"... Natl. Aniline dz.

Chem. Co. "Novonacco NN Do. "Sautomerse". Monsanto Chemical Co. Solvedine NC'L Ciba Co., Inc. Ultravon, K, W Do. Sulfonated hydrocarbon..- "Sullatste Glgcol Products 0. CLASS IL-Alcohol sulfate, having 8 or more carbon mm x Octyl sodium sulfate. Octgalecuyl sodium sul- "Gardinol LS". E. I. du Pont.

a Dodecyl sodium sulfate." Gardinol WA". Do. Fatty alcohol sulfates- Dreue" Proctor dz Gamble.

"Du uol L-l44, E. l. du Pout.

D, LS, ME, 08, WA, T, WS, 80. Merpol B, 0''... Do. "Modiual T".. D0.

Formula Trade name 7 Manufacturer Cues IIL-Yjalion-actlu material:

Cetyl pyridinium bromide. Lauryl trlmethyl ammonium bromide (and these compounds described in Polak U. 8. Patent 2,125,031). I Quaternary ammonium "Triton S-l8 Rohm & Haas Co. The fatt acid salt of tri- Trlmethylol Commercial Solmethy olamiuo metha m i u o m e t h vents Corp. one. ane."

CLASS IV. Modifled sulfaled fatty acid eaten v Oleic acid ester of an all- I g e p o 11 AP General Dyestuffs phatlc compound. Extra." Corp.

Cues V.Derlvalivca of fatty acid amides Fatty acid amides "Igepon T" General Dyestufls orp. "Intramine Synthetic Chemica s. "Sapamine A" Ciba Co., Inc.

CLASS VL-Sulfonated ethera Suliouated ethers Tensol" SyInthetic Chem.,

1'10. Triton W 30. Rohm & Haas Co. "Triton 720, 8l2". D0.

CLASS VII.Miscellaneour and anclam'flable.

Aresket" Monsanto Chemical Co. Aresklene Do. Neopen SS" E. I. du Pout. Aerosol 0S" American Cyauamide and Chemcal Corp. DacouoY'. S A. Day Mfg 0., Inc. Darvan" R. T. Vanderbilt Co.,- nc. Daxad". Dewey dz Almy Chem. 00. "N. S. A. E." 01 Oil 6: Chem.

0. "Wetsit Jagques Wolf 6: U

o. "Aryleue" Hart Products Corp. "Ultra Wet Atantie Refining o. Nopco i967 Naatl. Oil Products 0. Dupouol 80".... E. I. du Pout. "Avirol 80". D0. ComiuoY' Commonwealth Color & Chemi- DetauoP cal 00. "Lanaclarin LM" E. l. du Pont. Lightning Peue- Commonwealth trator X". Color & Chemical 00. .Maproruiu". Onjyx Oil 6; Chem.

0. "Orvus WA" Proctor & Gamble. Soapatol".; Commonwealth Color 6: Chemical 00. "Fixanol" E. I. du Pont. Product QB Do. Di x" Stauco, Inc.

"Peuetrex' Maproflx" .I.

Hornkemd and 3 A C. Horn 00. Hercules Powder Co. Onyx Oil 6: Chem.

- Do. Rohm dz Haas Co.

Onyx Oil 6: Chem.

' Do. Carbide 6: Carbon Chem.

Admittedly, surface-active agents, such as above disclosed, have previously been added to coagulating baths in conventional viscose spinning processes. Heretofore, however, such materials have been added to coagulating baths in conventional spinning processes for the spinning of straight filaments. Such surface-active materials have previously been added to coagulating baths for the purpose of obtaining improved spinning of straight filaments, for example, to obtain a faster coagulation of the viscose in the coagulating bath, and for the reduction or elimination of spinneret cratering, or the elimination of clogging of spinneret openings. Spinneret cratering or spinneret clogging, if permitted to exist, will result in broken filaments or the production of small, under-size filaments. Yarns produced under these circumstances are decidedly inferior. In the crimp-spinning of crimpy filaments, however, the gradual discontinuation of V the formationof crimps in the filaments is not due to slow coagulation of the viscose, or to clogged spinneret openings, or to craters. The problems involved in the crimp-spinning process above described do not result in the breaking of filaments but involve merely a discontinuation of crimp formation. These latter processes are therefore not concerned with the usual factors of spinning straight'filaments and therefore it could not be foreseen that the addition of surfaceactive agents to a coagulating bath of a crimpspinning process would preserve the continuity of crimp formation in the filaments.

The quantity of surface-active agents to be incorporated in the coagulating bath of a crimpspinning process is relatively small, based on the total bath ingredients, being of the order of 0. up to 0.5%, while larger quantities may be employed if the surface-active agent is suificiently soluble.

Although the surface-active agents used in accordance with the present invention as crimpcontinuity preserving agents will decrease the measured surface tension of the coagulating bath, it is not known what part, if any, the lowering of surface tension may play in preserving the continuity of crimp formation in the spinning process. There is undoubtedly more to the phenomena of preserving the crimp-continuity of spinning than the mere lowering of surface tension. Attention is directed to the fact that in order to impart maximum preservation of crimpcontinuity it is necessary to use a quantity of surface-active agent which is distinctly in excess of that quantity merely required to give a maximum lowering of the surface tension of the bath. For example, 0.01% of a certain surface-active material is known to give maximum lowering of the surface tension in a coagulating bath. In order to achieve the desired preservation of crimp-continuity, it was found necessary to employ 5 to times the quantity of a surfaceactive agent known to give a maximum of the lowering of the surface tension. That is to say, it is necessary to use from 0.05% to 0.1% of the surface-active agent. Generally, quantities of the surface-active agents in excess of 0.01% will eifect substantially no further lowering of the surface tension in a coagulating bath, whereas quantities considerably in excess of that amount profoundly affect the length of time in which the spinning process will function to uniformly of lowering of the surface tension and improvement in the spinning of crimpy filaments to be realized by the" use of specific surface-active agents. For example, it has been observed that although octyl sodium sulfate will lower the surface tension to nearly 30 dynes per square centimeter as compared to Nacconol NR," which lowers the surface tension .to only 40 dynes per square centimeter, the latter material is superior to the former in preserving the continuity of spinning of crimpy filaments. The manner in which surface-active agents function to preserve continuity of spinning of crimpy filaments is therefore completely unknown.

It has furthermore been found that the surface-active agents will function to preserve the continuity of crimp formation in filaments to a greater extent if the coagulating bath contains an appreciable quantity of hydrogen sulfide. The presence of at least 28 parts per million by weight of hydrogen sulfide in the'bath will not in itself preserve the continuity of crimp formation, but will improve the results to be obtained when using a surface-active agent for-this purpose.

As above indicated, a coagulating or setting bath in which crimpy filaments of good strength are formed by spinning with a high jet velocitydraw-oif ratio must be a fast coagulating bath with no regenerating action, or, alternatively, one with a slow or delayed regenerating action. The preferred coagulating baths, employed in accordance with the present invention, are substantially the same as those described in our copending application above referred to, with the exception that a crimp-continuity preserving agent is added thereto. A fast coagulating non-regenerating bath will comprise a high concentration of a highly soluble salt or a high concentrationof a weak acid containing such a small amount of water as to give a strong dehydrating or precipitating action. An aqueous, saturated, or nearly saturated ammonium sulfate bath at approximately C. constitutes an excellent coagulating bath for the present process. Other highly soluble ammonium salts can also be used in high concentrations as well as other coagulating salt solutions such as asaturated sodium sulfate solution.

In a single setting bath spinning process, with which the present invention is most concerned, the setting bath should be slightly acid in character so as to have a slow or delayed regenerating effect on the viscose extruded thereinto. A preferred setting bath for such a process contains at least 5%-10% or more of ammonium sulfate together with sufiicient sodium sulfate to make the total salt content of the bath 15%, or greater, of the total bath ingredients including the water. The total salt content of the bath should be at least 2-3 times that of the total acid employed. The total salt content must be higher with high acid content and may be lower with low acid content.

As a general rule, baths which operate to produce filaments which are substantially smooth and non-crenulated, as opposed to the highly crenulated filaments produced by baths conventionally employed in the spinning of straight filament viscose rayon, are suitable for use in spin a crimpy filament. It has been found, in

all cases, that the surface-active agent, for the purposes of the present invention, must be used distinctly in excess of that required to give the maximum lowering of surface tension of the bath.

Attention is further directed to the fact that there is no direct correlation between theextent accordance with the present invention. The production of substantially smooth and non-crenuiated filaments in a bath is a definite indication that the bath is functioning to substantially complete the coagulation of the filaments before any substantial regeneration thereof.

Similar to the process defined in the above I illustrate the details of spinning permanently.

crimpy filaments in accordance with the present invention. It is to be understood that the invention is not to be limited to the specific details setiorth in these examples.

Example I A viscosemade from wood pulp containing 7% cellulose and 4% sodium hydroxide at a sodium chloride index of 4.0 was extruded through noble metal alloy spinneret having 100 holes, each hole being 0.002 inch in diameter, into a spinning bath having a j composition of 3.38% sulfuric acid, 15.35% ammonium sulfate, 7.85% sodium sulfate,

' and0.2 isopro pylnaphthalene sodium sulfonatel (fAlkanol B). The temperature of the 'bath was' maintained at about 47% C. The viscose delivery was 2025 grams per minute and the I crimpy yarn formed spontaneously at the spinneret was drawn. away from the spinneret at the rate of504 inches per minute after 48 inches of travel irrithe bath and was then-stretched 75% (based on the straight length of. the filaments) between. rubber nip rolls followed by relaxation under no tension. After one hour time lag to insurecornplete regeneration, the crimpy yarn was then washed free from acid and then rinsed with approximately 0.25% sodium carbonate soaaewmc rate of 456 inches per minute, and then stretched 50% between rubber nip rolls, followed by relaxation under no tension. The yarn, after one hour time lag to insure complete regeneration, was washed free from acid, using soft water. The acid free yarn was then rinsed with 0.25% sodium carbonate solution at 95 C. to remove free sulfur and then washed free of alkali, using lutionat 95 C. inorder to remove free sulfur,

followed by a washwith soft water to remove residual alkali. The purified yarn was then finishedwith approximatelyg0.5%. aqueous sulfonated olivefoil solution-'at 60? C. followed by drying in arelaxedconditiomwith the filaments freetoshrihk; p

-, Theyarn possessed a good permanent crimp,

was strongjand had "a smooth or substantially non-cren'ulated cross section with many of the filaments substantially round.

In this experiment, the ratio of nozzle velocity to the ratev at-which the thread was drawn awayv from the -spinneret was approximately 7.2. The

Alkanol B. requiredin-the above bath, to attain 1 maximumlowering-of the surface tension, is approximately 0.003%,--'while it was found essential to-sat isfactorilyrolong crimp-spinning to 'use approximately 0.20% -Alkanol- B.

Example I! A viscose prepared fromwood pulp containing -'7% cellulose and 6% sodium hydroxide at a so- .dium chloride index of 4.0 was extruded into spinning bath 'having a composition of 4.69% sulfuric acid ,..11.22%' ammonium sulfate, 8.8% sodium sulfate, andg0.20% Alkanol B at C. Spinning nozzles ,made from noble metal alloys,

having- '70 holes, each hole being 0.002 inch in diameter, were used in this example with a viscose delivery of 19.04 grams per minute. The crimpy yarn was formed spontaneously at the spinneret and was drawn away from the spinneret after 48 inches travel in the bath at the and non-crenulated cross section.

soft water. The purified yarn was then finished with an aqueous dispersion of 0.5 gram per liter of sulfonated olive oil at 60 C. After removal of excessive liquorin a centrifuge it was then dried in a relaxed condition in order to permit shrinkage of the individual filaments. Using the above spinning conditions, the ratio of nozzle velocity of the viscose to the rate of yarn drawn away from the spinneret was approximately 10.4. In the above spinning bath, the amount of Alkanol B" required to obtain maximum lowering of the surface tension was approximately 0.0025% while the amount required to obtain a satisfactorily increased crimp-spinning was approximately 0.20%. The resulting yarn possessed a substantially smooth non-crenulated cross section, possessed a good permanent crimp.

Example III Viscose made from cotton linters containing 7% cellulose and 6% sodium hydroxide at a salt index of 3.9 was extruded through noble metal alloy spinnerets having holes, each hole being 0.0025" indiameter, into a spinning bath having a composition of 2% sulfuric .acid, 11% ammonium sulfate, 11% sodium sulfate, and 0.20% lauryl trirnethyl ammonium bromide at a spinning bath temperature of 43 C. The viscose was extruded through the above spinneret at the rate of 26.9 grams per minute, which represents a nozzle velocity of approximately 3010 inches per minute. The crimpy yarn formed spontaneously at the spinneret was drawn away from the spinneret at the rate of 324 inches per minute followed by relaxing under no tension. After one hour time lag to insure complete regeneration of the above filaments they were washed free from acid, desulfured, washed free from alkali, finished and dried in the same manner as in Example II above. The yarn possessed a good permanent. crimp and a substantially smooth 7 Using the above surface-active material in the spinning bath, it was'possible to spin 6 hours or more before failure of formation of satisfactorily crimpedfilaments, while without the use of the above material, after spinning for from 3 to 10 minutes, satisfactory crimps were no longer formed in-the filaments. The ratio of nozzle velocity to'the rate at which the yarn was drawn away from the spinneret was approximately 9.29. The amount of surface-active material required to obtain maximum lowering of the surface tension was approximately 0.003% while it was found necessary to use approximately 0.20% of the above material in order to satisfactorily prolong crimp-spinning.

Example IV Viscose made from wood pulp having the composition 7% cellulose and 6% sodium hydroxide at a sodium chloride index of 4.0 was extruded at the rate of 140 grams per minute through noble metal alloy spinnerets having 400 holes, each hole being 0.003" in diameter, intoa spinning bath having the composition 8.44% H2304, 37.65% ammonium sulfate, 2.5% sodium sulfate, and 0.1% Nacconol NR," at 45 C. The crimpy filaments, which formed spontaneously at the spinneret, were drawn away from the spinneret through 24 inches of bath at the rate of 41% inches per minute, and immediately stretched 59.5% between rubber nip rollers followed by relaxation. After a 3 minute time lag to insure complete regeneration of the filaments, the crimpy yarn was purified, finished and dried in the same manner as the above examples. The

resulting dry yarn possessed a good permanent crimp, was strong and had a smooth substantially non-crenulated cross section. The nozzle velocity in this spinning experiment was approximately 2910 inches per minute; hence the ratio of nozzle velocity to the rate at which'the filaments were drawn away from the spinneret was approximately 7.03. The amount of hlacconol NR. in the above bath required to obtain maximum lowering of the surface tension was approximately 0.01% while we found it necessary to add approximately 0.10% in the above spinfning both in order to satisfactorily maintain crimp-spinning conditions.

Example V Viscose made from wood pulp containing 7% cellulose and 4% sodium hydroxide at a chloride index of 4.0 was extruded through noble metal alloy spinnerets having 100 holes, each hole being 0.0025" in diameter, at the rate of 30.6 grams per minute into a bath having the composition 3.42% H2804, suflicient sodium sul fate to produce a saturated solution, and 0.2% Nacconol NR at C. The crimpy filaments formed spontaneously at the spinneret were drawn away from the spinneret through 60 inches of bath at the rate of 300 inches per minute, and immediately stretched between rubber nip rolls followed by relaxing. After a one hour time lag to insure complete regeneration of the yarn, it was purified, finished and dried in the same manner as in the above example. The dry yarn was strong, well crimped and had a substantially smooth and non-crenulated cross section. The ratio of the rate of extrusion of the viscose to the rate at which the crimpy filaments were drawn away from the spinneret was approximately 11.3. The amount of Nacconol NR required to obtain maximum lowering of the surface tension in the above spinning bath is approximately 0.02%, while it was found necessary to have approximately 0.2% Nacconol NR present to satisfactorily maintain crimp-spinning conditions.

Crimp-spinning processes, that is, processes in which a crimp is directly spun into the filaments by a high jet velocity-draw-ofi ratio with a fast coagulating, slow regenerating, or nonregenerating bath, can be made to spin crimpy filaments for a longer continuous period of time by including in the coagulating bath a crimpcontinuity preserving agent in accordance with the present invention. The preservation of crimp-formation in the filaments is sufiiciently prolonged that single-bath crimp-spinning processes can now be employed in plant production more economically than the two-bath processes as used prior to the present invention.

Since it is obvious that many changes and modifications can be made in the details set forth above without departing from the nature and spirit of the invention, it is to be understood that the invenion is not to be limited to these details except as set forth in the folowing claims.

We claim:

1. The process of crimp-spinning crimpy filaments which comprises extruding viscose, in the form of filaments, into a setting bath which has a sufilciently rapid coagulating action, relative to any regenerating action thereof, to completely coagulate said filaments prior to any substantial regeneration thereof, and drawing said filaments from the point where they are extruded into the bath, the velocity of extrusion being at least 4 times the velocity of the draw-off, said coagulating bath containing dissolved therein, as a crimp-continuity preserving agent, at least 0.05% of surface-active material having a solubility of at least 0.01% by weight in a 5% aqueous solution of sulfuric acid whereby to increase the continuity of uniform crimp formation in the spun filaments.

2. The process of crimp-spinning crimpy filaments as defined in claim 1, in which .the setting bath has a coagulating and regenerating action.

3. The process of crimp-spinning crimpy filaments as defined in claim 1, in which the setting bath has a coagulating, non-regenerating action.

4. The process of crimp-spinning crimpy filaments which comprises extruding viscose, in the form of filaments, into a setting bath which has a sufficiently rapid coagulating action, relative to any regenerating action thereof, to completely coagulate said filaments prior to any substantial regeneration thereof, drawing said filaments from the point where they are extruded into-the bath, the velocity of extrusion being at least 4 times the velocity of draw-ofi, said coagulating bat-h containing dissolved therein, as a crimpcontinuity preserving agent, at least 0.05% of a surface-active material having a solubility of at least 0.01% by weight in a 5% aqueous solution of sulfuric acid whereby to increase the continuity of uniform crimp formation in the spun filaments, and stretching said coagulated filaments in the wet state.

5. The process of crimp-spinning crimpy filaments as defined in claim 4, in which the setting bath has a coagulating and regenerating action.

6. The process of crimp-spinning crimpy filaments which comprises extruding viscose in the form of filaments into a setting bath which has a sufiiciently rapid coagulating action, relative to any regenerating action thereof, to completely coagulate said filaments prior to any substantial regeneration thereof, drawing said filaments from the point where they are extruded into the bath, the velocity of the extrusion being at least 4 times the velocity of draw-off, said coagulating bath containing dissolved therein, as a crimpcontinuity preserving agent, at least 0.05% of a surface-active material having a solubility of at least 0.10% by weight in a 5% aqueous solution of sulfuric acid whereby to increase the continuity of uniform crimp formation in the spun filaments, regenerating said filaments, and stretching the samewhile they are in the wet state.

'I. The process of crimp-spinning crimpy filaments as defined in claim 6, in which the setting bath has a coagulating and regenerating action.

8. The process of crimp-spinning crimpy filaments as defined in claim 1, in which the surfaceactive material comprises a sulfonic acid salt.

9. The process of crimp-spinning crimpy filaments as defined in claim 1, in which the coagulating bath contains at least 28 parts per million, by weight, of hydrogen sulfide.

10. The process of crimp-spinning crimpy filaments which comprises extruding viscose, in the form of filaments, into a setting bath which has a sufiiciently rapid coagulating action, relative to any regenerating action thereof, to completely coagulate said filaments prior to any substantial regeneration thereof, drawing said filaments from the point where they are extruded into the bath, the velocity of extrusion being at least 4 times the velocity of draw-oil, stretching said filaments while they are still wet with said coagulating bath liquid, and relaxing said filaments in the absence of tension, said coagulating bath containing dissolved therein, as a crimp-continuity preserving agent, at least 0.05% of a surfaceactive material having a solubility of at least 0.01% by weight in a 5% aqueous solution of sulfuric acid whereby to increase the continuity of uniform crimp formation in the spun filaments.

11. The process of crimp-spinning crimpy filaments as defined in claim 10, in which the setting bath has a coagulating and regenerating action.

12. The process of crimp-spinning crimpy filaments as defined in claim 10, in which the suroil, stretching said filaments while still wet. with coagulating bath liquid, relaxing said filaments in the absence of tension for a sufllcient period of time to insure complete regeneration by the coagulating bath liquid contained therein, said coagulating bath containing dissolved therein, as a crimp-continuity preserving agent, at least 0.05% of a surface-active material having a solubility of at least 0.01% by weight in a 5% aqueous solution of sulfuric acid whereby to increase the continuity of uniform "crimp formation in the spun filaments.

14. The process of crimp-spinning crimpy filaments as defined in claim 13, in which the surface-active material comprises a sulfonic acid salt. 

